feat: add c implementation of heaviside

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Author: sahil20021008

lib/node_modules/@stdlib/math/base/special/heaviside/README.md

@@ -2,7 +2,7 @@
 
 @license Apache-2.0
 
-Copyright (c) 2025 The Stdlib Authors.
+Copyright (c) 2018 The Stdlib Authors.
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -20,7 +20,7 @@ limitations under the License.
 
 # Heaviside Function
 
-> Evaluate the [Heaviside function][heaviside-function].
+> Evaluates the [Heaviside function][heaviside-function].
 
 <section class="intro">
 
@@ -190,9 +190,9 @@ logEachMap( 'H(%0.4f) = %0.4f', x, heaviside );
 #include "stdlib/math/base/special/heaviside.h"
 ```
 
-#### stdlib_base_heaviside( x )
+#### stdlib_base_heaviside( x, continuity )
 
-Evaluate the [Heaviside function][heaviside-function].
+Evaluates the [Heaviside function][heaviside-function].
 
 ```c
 double out = stdlib_base_heaviside( 0.0, 0 );

lib/node_modules/@stdlib/math/base/special/heaviside/benchmark/c/Makefile

@@ -1,7 +1,7 @@
 #/
 # @license Apache-2.0
 #
-# Copyright (c) 2025 The Stdlib Authors.
+# Copyright (c) 2018 The Stdlib Authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.

lib/node_modules/@stdlib/math/base/special/heaviside/benchmark/c/benchmark.c

@@ -1,7 +1,7 @@
 /**
 * @license Apache-2.0
 *
-* Copyright (c) 2025 The Stdlib Authors.
+* Copyright (c) 2018 The Stdlib Authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.

lib/node_modules/@stdlib/math/base/special/heaviside/docs/types/test.ts

@@ -23,7 +23,7 @@ import heaviside = require( './index' );
 
 // The function returns a number...
 {
-	heaviside( 3.141592653589793, 'half-maximum' ); // $ExpectType number
+	heaviside( 3.141592653589793 ); // $ExpectType number
 	heaviside( 0, 'half-maximum' ); // $ExpectType number
 	heaviside( 0, 'left-continuous' ); // $ExpectType number
 	heaviside( 0, 'right-continuous' ); // $ExpectType number

lib/node_modules/@stdlib/math/base/special/heaviside/src/main.c

@@ -22,9 +22,9 @@
 /**
 * Evaluates the Heaviside function.
 *
-* @param x 				input value
-* @param continuity 	continuity option
-* @return				function value
+* @param x              input value
+* @param continuity     continuity option
+* @return               function value
 *
 * @example
 * double v = stdlib_base_heaviside( 3.14, 0 );
@@ -55,7 +55,7 @@
 * // returns NaN
 */
 double stdlib_base_heaviside( const double x, int continuity ) {
-	if ( stdlib_base_is_nan( x )) {
+	if ( stdlib_base_is_nan( x ) ) {
 		return 0.0/0.0;
 	}
 	if ( x > 0.0 ) {